Marilyn Tan, M.D.
NPI 1770899395 · Endocrinology, Diabetes & Metabolism Physician · Stanford, CA
Enrolled with Medicare as Practitioner - Endocrinology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marilyn Tan, M.D. is a Endocrinology, Diabetes & Metabolism Physician provider in Stanford, CA (NPI 1770899395).
Provider details
- NPI number
- 1770899395
- Entity type
- Individual
- Primary specialty
- Endocrinology, Diabetes & Metabolism PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
- License
- A113366 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
15 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
2,226 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 802 | $89 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 378 | $154 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 237 | $19 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 232 | $133 |
| Continuous Monitoring of Blood Sugar Level in Tissue Fluid Using Sensor Under Skin With Interpretation and Report95251 | 209 | $39 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 42 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Levothyroxine Sodium | 277 | 73 |
| Dulaglutidebrand: Trulicity | 179 | 34 |
| Tirzepatidebrand: Mounjaro | 175 | 29 |
| Metformin Hcl | 150 | 42 |
| Semaglutidebrand: Ozempic | 117 | 29 |
| Glipizide | 117 | 39 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$3,951 across 5 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2010-08-19
- Last updated
- 2024-04-17
- Certified
- 2024-04-17
Frequently asked questions
- What is Marilyn Tan's NPI number?
- Marilyn Tan's National Provider Identifier (NPI) is 1770899395, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marilyn Tan's specialty?
- Marilyn Tan is listed in the NPPES registry with a primary specialty of Endocrinology, Diabetes & Metabolism Physician (Allopathic & Osteopathic Physicians).
- Where is Marilyn Tan located?
- Marilyn Tan's practice location on file with NPPES is 300 Pasteur Dr, Stanford, CA 94305-2200.
- What is Marilyn Tan's phone number?
- The practice phone number listed in the NPPES registry for Marilyn Tan is (650) 723-4000.
- Does Marilyn Tan accept Medicare?
- Marilyn Tan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marilyn Tan's NPI active?
- Yes — Marilyn Tan's NPI (1770899395) is active in the NPPES registry as of the last update on 2024-04-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.